OT but in OP's firefly render settings I'm seeing something peculiar there with the pixel sample settings. I don't think I've seen, in all my years, anyone use a setting above 10 for those settings, I myself have never gone past 8. Bagginsbill would typically use 6 or 7, IIRC, for final production render.

Perhaps the OP is also aware that setting the min shading rate to .10 in render settings will only show an improvement in detail if all actors are likewise set at .10 in their properties. The render settings value will only work if it matches each actors individual setting, it isn't an override. The actor properties value is what will be used during render. So you would have to go into every body part of your figure's properties and change from the default 0.20 to .10. This can get very tedious, I myself use a script to make the scene global changes in all actors if I want to use a value other than the default 0.20

You also will find that setting your Post Filter Type to Sinc and Post Filter Size to 2 will result in crisper more detailed renders.